Climate change and farming: Growing seasons getting longer

BOISE -
This week the National Oceanic and Atmospheric Administration released numbers that showed the average global temperature for January through April of this year were the second warmest for this period in 138 years of keeping records, just behind last year's record-setting January to April stretch.

Warmer temperatures, however, don't always mean doom and gloom when it comes to farming in the Treasure Valley.

Wine grapes have been grown in Idaho since the 1960s but in just the last two decades, wineries have grown from about a dozen to more than 50.

A lot of that has to do with economics but a big part is tied to a temperature trend that continues to go up.

"So what are the greenhouse gases again, we talked about 'em," asks Jen Pierce in the middle of a field behind Middleton Middle School.

"Methane, good, those are some of the big ones, okay?" Pierce says after the response from the 6th grade class.

Pierce, an associate professor at Boise State University with a PhD in Geology, and a focus on climate change, is giving a lesson in greenhouse gases.

"Okay, shortwaves, you ready?" asks Pierce, as she begins a game to demonstrate how gases get trapped in the atmosphere.

"Marks, get set, go!"

She says knowing what shortwave and longwave radiation does will help these students understand what has been happening with the earth for eons.

"Did those shortwaves get stuck in the atmosphere?" Pierce asks the kids.

"We have data on changes in our climate going back for billions of years," she says.

But it's the most recent data that Pierce is preaching today.

"Since about the late 1800s, the average temperature of the Earth has gone up by about 1.5 degrees Fahrenheit," recites Pierce.

That may seem like a lot but it's a number that's significant to Mike Williamson. His family has been farming near Marsing for more than 100 years.

The Sunny Slope area has long been a fruitful place to grow fruit and Williamson orchards have produced peaches, apples, and cherries for four generations.

But in 1998, Williamson says, they made their first foray into grapes, starting with just 12 acres. Today 55 acres that used to grow alfalfa and be filled with fruit trees have been converted to vineyards with 8 different varieties.

"Vineyards are a story of time," begins Williamson.

And what time has shown him is that Sunny Slope has become more agreeable to grape growing because of warmer temperatures.

"That's what we're finding out," he says.

Williamson points out he's been watching when the bud breaks on the vine in the spring.

"It's been coming earlier and the harvest has been able to be stretched later."

In fact, according to research by Southern Oregon University, the growing season, the time between the last frost in the spring and the first in the fall, is 13 days longer than it was in the early 20th century.

That gives grapes more time to mature and has made Williamson's move to wine less of a financial risk.

"I think we are able to ripen and get that high quality more frequently," he says.

So further expansion is part of his plan and he's even considering planting grapes that typically are only grown in Mediterranean climates.

"If we can get similar (temperatures) to traditional growing areas in Europe then we're going to try it," he admits.

Which is why Williamson sees the future of farming here being tied to change.

"The climate is changing in increments," says Williamson. "I think our behavior is probably going to change in increments as well."

Back at the middle school, adaptation is also part of the lesson plan for Pierce, a fate that falls on the next generation.

"And they're really optimistic about what they can do," Pierce says, referring to her students. "And they're excited about it."

Variability is also a problem with climate change, according to Pierce, meaning the extreme swings in conditions come more frequently - and that can be a problem when predicting what to expect for farming.